Hydraulic piping structures for supplying pressure oil to cylinders for controlling the boom, arm and bucket of a backhoe are disclosed in Japanese Utility Model Publications Kokai Nos. 61-80852 and 63-76050. These piping structures include hydraulic hoses extending in an upwardly curved form from a joint disposed on a surface of a swivel deck at a position laterally displaced from a swing bracket, to a terminal mounted on an upper face of a proximal end portion of the boom. Hydraulic hoses for controlling the boom extend in the upwardly curved form from the boom cylinder to be directly connected to the terminal on the swivel deck.
In the known structures noted above, the joint mounted on the swivel deck is laterally displaced from the swing bracket, which requires the curved portions of the hydraulic hoses to have additional slack lengths to accommodate sideways swings of the boom as well. Compared with the case where the joint is disposed directly rearwardly of the swing bracket, the hydraulic hoses have longer and higher curved portions. Such hoses could obstruct the driver's field of view, making it difficult for the driver to carry out a required operation.